For the best atheists agree with the best defenders of faith on one crucialpoint: that the choice to believe or disbelieve is existentially the most important choice of all. It shapes one's whole understanding of human life and purpose, because it is a choice that each of us must make for him or herself. To impress on a man the urgency of that choice, Kierkegaard wrote, it would be useful to "get him seated on a horse and the horse made to take fright and gallop wildly ... this is what existence is like if one is to become consciously aware of it."

Mr. Dennett would have benefited from a ride on Kierkegaard's horse. For what dooms his book, not just in literary but in logical terms, is his complete failure to recognize the existential demand of religion. "I decided some time ago," he writes, "that diminishing returns had set in on the arguments about God's existence," and so he leaves God out of his argument entirely .... Mr. Dennett proceeds to analyze religion anthropologically, as a behavior, an institution, and an aesthetic taste. But .... the definition so completely misses the actual substance of religious experience....